'small' impact driver

Personally, I'd go for a good quality posidriver. Maybe going up one size
and gently tapping it home so there's little chance of it slipping out
(f'narr).

I'd REALLY hesitate to use an impact driver on something made of zinc and
knob cheese.


--
Beav

VN 750
Zed 1000
OMF# 19

 

Only if you count north west Leicestershire as the north. My old Vintage
racing mate always used the term. Thrutch = torque.

--
+----------------------------------------------------------------+
| Pete Fisher at Home: |
| Voxan Roadster [ SPACE ! ] Yamaha WR250Z |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+----------------------------------------------------------------+

 

I have no plaster cast but have been on anti-biotics for a week, up
until yesterday. Tonight I will be quite happy if I end up throwing
beer & curry all over myself. In fact, it's a goal.

 

http://www.urbandictionary.com/define.php?term=Thrutch

Seems to be a well fitting word.

 

What there's zinc in them?

 

No, no. Thrutching is what you do when you're trying to get through a
flat out crawl in a cave.

 

Or climbing. Using brute force instead of technique is sometimes
referred to as thrutching (or thugging) your way over a move/up a
route.

 

Ooh, thats a smart idea. I'll lodge that one away in my darkest recesses for
future use.

 

I learnt it from my mentor as an apprentice mechanic. I reckon he
could be described as a vintage northern pervert, so pretty much all
the boxes appear to have been ticked.

Paul.

 

Well of course pozidrive screw heads are a different
profile from phillips - maybe that is the idea though?

I was horrified to notice recently that phillips head screws
are *designed* to limit the torque transmitted from the
driver to the screw. The idea is to prevent damage
from ham-fisted operators during assembly. Of course this
turns out to mean that they are also *designed* not
to come undone with normal screwdrivers after they have
been installed for a while. You need something to
hold the driver in while the rotational force is applied
or to use some other method to "persuade" it to
release

http://en.wikipedia.org/wiki/Henry_F._Phillips
"The design was purposely made to cam out"

# # #

Coefficient of expansion of various metals
http://metals.about.com/gi/dynamic/...yharmancanada.com/TheBrazingBook/comparis.htm

Range
Zinc & its Alloys 19.3 10.8
Aluminum & its Alloys 13.7 11.7
Alloy Steels 8.6 6.3

See the article if you care about the units.

It is certainly the case that alluminium alloys have a
usefully higher coefficient of expansion than steel
with respect to releasing stuck stuff. Zinc alloys
seem to have an even larger coefficiant of expansion
and so the effect should be greater.

Even boiling water will have an effect. Don't get scalded.

 

Don't know about northern, but it's a common enough word usually used to
describe a hard time on the bog.


--
Beav

VN 750
Zed 1000
OMF# 19

 

Next to the knob cheese, of course.


--
Beav

VN 750
Zed 1000
OMF# 19

 

True enough, but they're interchangeable for the majority of jobs and a
Posidriver used on a Philips screw wn't hurt either the driver or the screw.

For tightening yes, not for undoing.

Nope. the shape of the screw slot is "one way" and will "allow" the driver
to come free of the screw without damaging it, but it does nothing to stop
HUGE amounts of torque being applied in reverse.

Like an impact driver?

Wike again, so it must be true. And it is, partially. I'm not bothering to
read what's in that link, but I suggest you try to discover what the term
"cam out" means and then apply it to what happens when the force is
reversed.


--
Beav

VN 750
Zed 1000
OMF# 19

 

Explosives and the bog? Brave fucker eh?

--
Beav

VN 750
Zed 1000
OMF# 19

 

Commonly used as a verb by climbers, meaning the technique which involves
jamming as much of your body as will go into a crack, then squirming in a
(hopefully) upward direction. Climbing walls don't generally have this
kind of move, so it might be becoming a bit obsolete.

 

Exactly, however the OP has described that he is
reluctant to bash his carburettor wiv a big hammer.

Hmmm.
Are you saying that the phillips screw/screwdriver is not
symmetric?

They sure look symmetric. They also very frequently
fail to remove screws that have been installed for a while.

My current view is that phillips head screws are simply
not designed to be removed for maintenance without
recourse to an impact driver or similar. If it happens that
an impact driver is not conveniently deployable
in any paricular situation then it appears that the
manufacturers view is - that's your problem matey.

While I am not presently involved in professional
vehicle maintance I do have substantial experiance
that supports the described view.

 

Ooh missus!

With the number of gays around, I seriously doubt it.


--
Beav

VN 750
Zed 1000
OMF# 19

 

As well he should be, but I was being just a little facetious.

Nothing's perfect, but you can apply more torque anti-clock than you can in
the clockwise. They don't cam out by design when undoing.

Your view is wrong then.

Why would they think anything esle though?

Ok, you win.

And it's "experience"


--
Beav

VN 750
Zed 1000
OMF# 19

 

I don't think this is true.

Float bowls are invariably held on with Phillips screws and I've never
had to use an impact driver to remove them. Sometimes, when they've been
severely stuck, I've had to grip the head in a pair of Mole grips to
turn it (as you suggested), but that's very rare.

Phillips scres on engine cases etc often need an impact driver because
they're in an exposed position to cop all the water and road crap,
whereas those used elsewhere aren't.